x-pipe for v6 mustang

my friend has a dual exhaust set up in his 96 v6 stang. i was wondering if an xpipe would offer beneficial gains or if they're only good for 8 and over cylinders. what other relatively inexpensive mods would you guys recommend?

He'd gain some hp from an x-pipe, maybe not as much as a V8 prob is most x-pipes dont have cats. So yuo friend wont be passin emissions

An X-Pipe helps alot. My friend has one has. It also makes the exhuast sound more like a V8